Bug fix in the SelectionManagerImageTexels.

When recovering texels in a SelectionProcessor, their ordering was flipped vertically.

GLViewer/SelectionManagerImageTexels.cpp

@@ -129,13 +129,13 @@ void SelectionManagerImageTexels::onUpdatingSelection( SelectionTool *tool )
         fbo.Bind();
 
         glBegin( GL_QUADS );
-            glTexCoord2i( 0, 1 );
+            glTexCoord2i( 0, 0 );
             glVertex2i( t->x     , t->y      );
-            glTexCoord2i( 1, 1 );
-            glVertex2i( t->x+t->w, t->y      );
             glTexCoord2i( 1, 0 );
+            glVertex2i( t->x+t->w, t->y      );
+            glTexCoord2i( 1, 1 );
             glVertex2i( t->x+t->w, t->y+t->h );
-            glTexCoord2i( 0, 0 );
+            glTexCoord2i( 0, 1 );
             glVertex2i( t->x     , t->y+t->h );
         glEnd();
         glFlush();
@@ -162,13 +162,13 @@ void SelectionManagerImageTexels::onDisplay( GLViewer *viewer,
         {
             t->tex.Bind( 0 );
             glBegin( GL_QUADS );
-                glTexCoord2i( 0, 1 );
+                glTexCoord2i( 0, 0 );
                 glVertex2i( t->x     , t->y      );
-                glTexCoord2i( 1, 1 );
-                glVertex2i( t->x+t->w, t->y      );
                 glTexCoord2i( 1, 0 );
+                glVertex2i( t->x+t->w, t->y      );
+                glTexCoord2i( 1, 1 );
                 glVertex2i( t->x+t->w, t->y+t->h );
-                glTexCoord2i( 0, 0 );
+                glTexCoord2i( 0, 1 );
                 glVertex2i( t->x     , t->y+t->h );
             glEnd();
             t->tex.Unbind();
@@ -199,15 +199,21 @@ bool SelectionManagerImageTexels::getSelectionMask( std::vector<uint8_t> &mask )
         {
             t->tex.DumpTo( selectionBuffer, GL_RED, GL_UNSIGNED_BYTE );
 
-            for( int i=t->y+t->h-1, n=0; i>=t->y; --i )
+            for( int i=t->y, n=0; i<t->y+t->h; ++i )
+            {
+                int row = (m_ImageHeight-i-1)*m_ImageWidth;
                 for( int j=t->x; j<t->x+t->w; ++j, ++n )
-                    mask[ i*m_ImageWidth + j ] = selectionBuffer[n];
+                    mask[ row + j ] = selectionBuffer[n];
+            }
         }
         else
         {
             for( int i=t->y; i<t->y+t->h; ++i )
+            {
+                int row = (m_ImageHeight-i-1)*m_ImageWidth;
                 for( int j=t->x; j<t->x+t->w; ++j )
-                    mask[ i*m_ImageWidth + j ] = 0;
+                    mask[ row + j ] = 0;
+            }
         }
 
     delete[] selectionBuffer;